Wall attachment fluidic device

ABSTRACT

Providing the attachment wall of a fluidic device interaction region downstream of the control port with laterally spaced parallel wall portions. The nonrectangular cross section provides areas of strong and weak wall attachment with the weak attachment flow being readily detached in response to low power control signals to pull the strong attachment flow from its laterally displaced wall.

3,030,979 4/1962 Reilly 10 Claims, 9 Drawing Figs.

US. Cl

Int.

Field of Search References Cited UNITED STATES PATENTS United States Patent n 13,552,416

[72] Inventor LynnG.Amos 3,148,691 9/1964 Greenblott l37/81.5 Powell, Tenn. 3,209,775 10/ 1 965 Dexter et al. 137/81.5 v[21] AppLNo. 820,202 3,246,863 4/1966 Posingies l37/81.5X 122] Filed' Apr.29, 1969 3,283,767 11/1966 Wright [37/815 -[45] Patented Jan.5,l971 3,294,103 12/1966 Bowles l37/8l.5 [73] Assignee CorningGlassWOrks 3,378,023 4/1968 Beeken 137/81.5 Corning, NY. 3,442,280 5/1969 Boothe 137/81.5

a corporation of New York Primary Examiner-Samuel Scott Attorney-Sughrue, Rothwell, Mion, Zinn and Macpeak ABSTRACT: Providing the attachment wall of a fluidic device interaction region downstream of the control port with laterally spaced parallel wall portions. The nonrectangular cross section provides areas of strong and weak wall attachment with the weak attachment flow being readily detached in response to low power control signals to pull the strong attachment flow from its laterally displaced wall.

PATENTEDJAN 51921 3552.416

- sum 1 [1F 2 FIG. y es 382 M 42 68 so INVENTOR 2 7 H6. 5 LYNN e. AMOS ATTORNEYJ: V

PATENTEUJAN 5|97|- I 3552, 116

-- SHEETEUFZ,

INVENTOR LYNN G. AMOS ATTORNEY;

WALLA'ITACIIMENT rLurmc nnvrcr:

BACKGROUND or rnrs INVENTION I .Field of the Invention This invention relates to I fluidic devices and more particularly to such devices of the wall attachment type in which, the power streamconventionallyattaehes itself to one wall or the other after entering the interactionregion. j t

2. Description of the Prior Art Wall attachment devices such'as fluidic amplifiers consist in general of a power nozzle discharging a power stream. into an interaction region, which is of generally rectangular cross section and having diverging sidewallsof some length and to one of which, the power stream attaches in theabsence of control signals. Conventionally, on opposite sides of the power stream, just downstream of the power nozzle inlet, there are provided one or more control ports-whose axesare at right angles tothe path 'ofthe power streams The power stream is moved from attachment position. withrespect to one wall to the other wall by providing a fluid pressure pulse .at the control port on the initial wall attachment side,i n which case, through momentum impact, the power stream is deflected from one wall-attachment position to-the'other by a control signal of substantially less power-than that of the power stream. Alter- 1 natively, a fluid pressure differential is created across the opposed control ports to cause the power strearn'to flip from one wall to the other.

3 As the power strea'rn enters the interaction chamber from the power'noz zle port, attachmentto the diverging side wall occurs at some point downstream of thenozzle opening and the adjacent rightangle control ports. The attached flow therefore switches from one wall to the otherby injecting a control flow. into the separation and moving the attachment of the power stream down thewall in the direction of fluid flow and off the end of the divergingsidewall. The gain of these devices (pressure orflow recovered in the outlets divided by control pressure or flow) is an important characteristic of the device, f

su AnY OF THE INVENTION This invention is directed to a wall attachmentfluidic device in which the interaction region, downstream of the power stream nozzle inlet, instead of being of rectangular cross section, has laterally "spaced and. parallel power stream attachmentwall portions. A fluid control signal at the control port adjacent the power stream of relativelylow power causes a portion of the power stream in weak attachment to that wall portion most remote from the center of the interaction passage. to detach itself from its wall, and to pull the remaining portion of the power stream from the other wall portion.

Preferabl the, interaction region of the chamber has diverging sidewalls in the direction of fluid flow andis l- 6 shaped in cross-sectional configuration. A power nozzle may have sidewalls converging in the direction of power stream flow whose cross sectional configuration may also be I-shaped i I to provide laterally spaced, parallel wall portions conforming 70 to those of the diverging interaction region. Alternatively, the cross-sectional configuration of the interaction chamber may be T.-shaped cross-shaped or any other nonrectangular cross section which willproduce a power stream having weakly-attached and strongly attached portions. i

BRIEF DESCRIPTION OF THE DRAWINGS region, with opposed control passages at right angles to the path-of the power stream.

FIG. 2 is a perspective view of a modified fluidic element block incorporating the nonrectangular cross section power stream passage of the present invention.

FIG. 3 is an elevational view of a-fluid amplifier of the wall attachmenttype employing the configured block of FIG. 2.

FIG. 4 is a plane view of the device shown in FIG. 3 with the cover. removed during operation, in the absence of a control signal.

FIG. Sis an enlarged plane view of a portion of the device shown in FIG. 4 under an applied fluid control signal at one of the control ports. v

FIG.-6 is an elevational view of a fluidic wall attachment device employing the present invention in modified form.

. 'FIG. 7 is an elevational view of a fluidic device incorporating yet a third embodiment of the present invention.

FIG.-'8 and 9 are cross-sectional views through interaction regions of further embodiments of the present invention.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring to FIG. 1 of the drawings, a typical prior art fluidic amplifier of the wall attachment type may include a configured block 12 which carries a converging power stream inlet passage or nozzle 14 and a diverging interaction region 16 downstream of the inlet nozzle and in line therewith. It is noted'that the cross-sectional configuration of both the inlet nozzle passage and the diverging interaction region is rectangular. A cover (not shown) completes the device 10. In conventional fashion, the diverging interaction region includes a pair of laterally spaced sidewalls l8 and 20 to which the fluid power stream (not shown) readily attaches itself, that is to one wall or the otherQThis depends upon chamber configuration in the absence of control signals applied to right angle control passages 22 and 24. Control ports 26 and 28 open up into the interaction region at the upstream end thereof, on either side of the power stream as it exits from; inlet nozzle port 30 and movesin the direction of arrow .32 through the diverging interaction region 16. Assuming a power stream is moving from the inlet nozzle through the interaction region and exiting therefrom in the direction of arrow 32 and further assuming that as the power stream exits from the interaction region, it is attached to the diverging wall 20, the attached flow is switched in conventional fashion from the wall 20 to wall 18 by introducing control flow into control passage 24 in which case, the control flow entering the separation bubble existing between the power stream and the upstream portion of wall 20 causes the separation bubble .to move downstream towards end 34 of this wall. Since the full power stream attaches itself to wall 20 which occupies a single plane, a control signal of given strength is required to move a power stream of given value to achieve detachment of the power stream from righthand control wall 20 and to switching to the left-hand control wall 18 where it reattaches itself.

In contrast to the prior art wall attachment device of FIG. 1, at least the interaction region of the wall attachment device of the present invention has other than a rectangular cross section with multiple attachment wall portions existing respectively in spaced parallel planes. Reference to the embodiment of FIGS. 2 through 5, discloses that a fluidic element 10 may be constructed of a basi: block 12' having configured passages such as a power stream inlet passage 14', a diverging I (not shown) are incorporated therewith. Note, however, in the instant device that the cross-sectional configuration of both the converging inlet passage or nozzle 14' or diverging interaction region 16' is, rather than rectangular in cross section, I-shaped such that one attachment wall of the interaction region is provided with a central, longitudinally extending attachment wall portion 38 and upper and lower laterally spaced and parallel sidewall portions 40. The opposite sidewall is similarly provided with a central diverging attachment wall portion 42 and upper and lower attachment wall portions 44 which are laterally offset and parallel therewith. Thus, as indicated in FIG. 3, the cross-sectional configuration of the interaction region is in the form of an I having a rather narrow central flow region or area B for the power stream and upper and lower rather wide flow regions or areas A on either side thereof.

In like fashion, it is noted that within the converging inlet nozzle passage 14, one side of the inlet nozzle is provided with a central wall portion 46 and upper and lower laterally offset sidewall portions 48, while on the opposite side of the same inlet nozzle, there is a wall portion in the center as at 50 which is laterally offset with respect to parallel sidewall portions 52 above and below.

During operation of the device, the effect of this configuration may be readily seen by reference to FIGS. 4 and 5 wherein cover 36 is removed for the sake of clarity. The power stream 54, such as a gas or liquid, entering converging inlet nozzle passage 14' results in the formation of three distinct flow portions within the diverging interaction region 16, a central, relatively narrow flow portion within flow area B as seen in FIG. 3 and upper and lower relatively wide flow portions within areas A as seen in FIG. 3. In this case, for the relatively wide portion of flow within region areas A, the point of wall attachment for this flow to wall 40 is shown at 56 while for the relatively narrow power stream flow portion within area B of the interaction chamber it is shown with respect to attachment wall portion 38 at 58, FIG. 4 in the absence of a control signal. For a given volume of flow therefor, in the absence of a fluid control wall attachment occurs near the downstream end 38 of wall portions 40 for areas A and at some point upstream therefrom for flow area B.

Referring next to FIG. 5, assuming that within control passage 24', a fluid signal of relatively small magnitude occurs, as indicated by arrow 60, fluid pressure is exerted at control port 62 for the portion of the power stream passing through the relatively wide upper and lower power stream flow areas A, in the diverging interaction region while, area 64 within the control passage 24' represents the control port for the much narrower portion of power stream flow within flow area B defined by spaced sidewall portions 38 and 42. It is noted that the magnitude of the control signal 60 is insufficient to displace the line of wall attachment for the power stream moving through interaction passage portion B, beyond the end 66 of central attachment sidewall 38, but however, insofar as sidewall portions 40 are concerned, the strength of the control signal 60 is sufficient to cause the A passage portions of the power stream to become detached from the diverging sidewall portions 40. This is because flow from the power nozzle l4 and attachment within the relatively wide areas A is characterized by low attachment strength due to the proximity ofthe top and bottom walls and the width between these walls, while flow in area B which is centrally located between these areas is sufficiently spaced from the top and bottom as to be uninfluenced thereby, and flow in area B thus has strong wall attachment.

The net effect of this is that this attachment of the low attachment strength flow in the upper and lower A regions, adjacent sidewall portions 40, exerts a viscous shear force of the main flow of fluid in the B region that tends to pull the B flow along with it from attachment line 53'. Since the flows in the A regions are low attachment flows, it takes very little control flow or signal strength to move their attachment lines 56 off the ends 68 of the wall portions 40, FIG. 5. If prior to the application of a control signal to one of the control ports, atmospheric pressure is operating on the power stream through both control passages 22' and 24', the atmospheric pressure tends to push the power stream flow portions A to the opposite attachment wall, the flow portions Attending to drag the flow portion B along therewith. After a small control flow is added as indicated at 60, the atmosphere helps in trying to detach the power stream flow within passage region' Bi The control flow needs only to be increasedvsli'gh'tly more before the combined action of the control flow and the-shear-force created by the unattached flow in regions-wAnon/ercomes'the main attachment force in region B to switclrlheafiow from the right-hand side to the left-hand side. z":

In actual practice, the I cross section shown in the device; of FIG. 2, in contrast to the conventional rectangular configuration device of FIG. 1, resulted in switching occurring at 50 percent less pressure for the control signal and 50 percent less flow for the power stream. Both devices operate below .5 p.s.i.

Instead of an interaction region and inlet nozzle which is I- shaped in cross section, these regions may have alternative cross-sectional configuration while providing the necessary laterally spaced and parallel wall. portions to define power stream flow of relative strong and weak wall attachment properties. Referring to FIG. 6 inan alternative form, the fluidic element 10" is again constructed ofa basic block 12" having a converging power stream inlet passage 14'', a diverging interaction region 16" and control passage 22 and 24 respectively. For both the converging inlet passage and the diverging interaction region rather than being'l-shaped in cross-sectional configuration, the passage 'is cross-shaped. On attachment wall is formed by a central longitudinally extending attachment wall portion 38 and upper and' lower laterally spaced and parallel sidewall portions 40". Theopposite sidewall is similarly provided with a central diverging attachment wall portion 42" and upper andlower attachment wall portions 44" which are laterally offset and parallel thereto.

In similar fashion within the converging inlet nozzle-passage 14" one side of the inlet nozzle is provided with a central wall portion 46", and upper and lower laterally offset sidewall portions 48", while on the opposite side of the same inlet nozzle there is central wall portion 50 which is laterally offset with respect to the parallel sidewall portions 52" above and below. In all other respects the device is identical both in operation and structure to the embodiment of FIGS. 2 through 5. Again, control signals of relatively small magnitude are sufficient to cause detachment of the power stream from the diverging sidewall portions 38" and 42".

The same results occurs in the embodiment of FIG. 7 wherein fluidic element 10" is formed principally by element block 12" having configured recesses forming inlet nozzle 14", diverging interaction region I6'-" and opposed control passages 22" and 24'. For both the inlet passage or nozzle 14" and the diverging interaction region 16" the cross-sectional configuration is T-shaped such that for the diverging interaction region 16", one attachment wall comprises upper and lower laterally spaced and parallel sidewall portions-38" and 40" respectively, while for the opposite attachment wall, portions 42" and 44" are parallel and laterally offset. This same relationship holes for the inlet nozzle whose walls are formed by portions 46", 48", 50" and 52" respectively. Again the operation is similar to that of the embodiments of FIGS. 2 and 6 in that a control stream of relatively low magnitude causes detachment of the portion of the power stream in contact with the attachment wall portion most remotefrom the axis of the flow passage which, subsequent to detachment, readily affects the remaining portion or portions of the power stream to flip the same to the opposite sidewall of the passage for reattachment. Again, in all other respects the embodiment of FIG. 7 is identical to that of FIG. 2. H

It is to be understood that cross-sectional configurations other than those disclosed may also produce the novel results disclosed hereinabove. For example, a gradual transition between the different flow regions is possible as well as" the abrupt transition regions which are disclosed. It is intended that this invention encompass any nonrectangular cross-sectional configuration which produces a power stream having weakly attached and strongly attached portions. FIGS. 8 and 9 are cross-sectional views of the interaction region of two fluidic devices in which the transition between the different flow regions is gradual. in FIG. 8, the walls of the interaction region are gradually curved, and in. FIG. 9, the walls have a V- shaped configuration.

The construction of the fluidic wall attachment device 10' is quite conventional. Fluidic devices in general, consist of laminar structures involving a configured block and a cover overlying the same with block and cover being. fonned of metallic, plastic, glass ceramics and like material. They may be transparent, translucent or opaque. The cover is securely attached in sealing relation to the underlying block by adhesive or the like. The cover is preferably bonded to the block by fusion. Block 12' may be formed with suitable flow passsages and/or apertures which mustbe formed" to a depth less than the block thickness since the block also acts as a bottom cover for the device. The configured portion of block 12' may be achieved by stamping, etching or any other conventional process. K

While the present invention has been particularly shown and described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes in the form and details may be made therein without departing from the spirit and scope of the invention.

lclairn: 1. In a wall attachment fluid amplifier including: a power stream inlet nozzle for issuing a power stream, an interaction region downstream and in line thereof and having at least one wall to which the power stream attaches itself and two parallel enclosing surfaces which intersect said at least one wall, 'a control port upstream of the point of power stream wall attachment for selectively switching the power stream therefrom, the improvement wherein said attachment wall consists of at leasttwo wall portions, said at least two wall por tions being spaced different distances from a plane which lies along the longitudinal axis of said power stream and is perpen-.

dicular to said enclosing surfaces, whereby a relatively low pressure l'luidcontrol signal at said control port causes said power stream portion attached to the wall portion most wherein said interaction region includes opposed. diverging,

planar sidewalls having a central wall portion offset laterally towards the center of said interaction region to form upper and lower laterally displaced sidewall portions adjacent said enclosing surfaces of said interaction region to create flow regions adjacent the top and bottom wall portions which are relatively wide with respect to the flow region between the central sidewall portions.

5. The fluidamplifier as claimed in claim 4 including opposed control ports on respective sides of the power stream,

downstream of the inlet nozzle and upstream of the wall attachment points for said power stream in the absence of a control signal.

6. Thefluid amplifier as claimed in claim 5 wherein said inlet nozzle includes serpentine sidewalls having laterally spaced sidewall portions and is l-shaped in cross section, corresponding to that of said interaction region.

7. The fluid amplifier as claimed in claim 1 wherein said interaction region comprises spaced diverging sidewalls and is T-sha ed in cross-sectional configuration.

8. he .fluid amplifier as claimed in claim 7 wherein the inlet nozzle includes serpentine sidewalls having laterally spaced sidewall portions and is T-shaped in cross section corresponding to that of saidinteraction region.

, 9. The fluid amplifier as claimed in claim 1 wherein the interaction region comprises spaced diverging sidewalls and is cross-shaped in cross-sectional configuration.

10. The fluid amplifier as claimed in claim 9 wherein said inlet nozzle includes serpentine sidewalls having laterally spaced sidewall portions and is cross-shaped in cross section corresponding to that of said interaction region. 

1. In a wall attachment fluid amplifier including: a power stream inlet nozzle for issuing a power stream, an interaction region downstream and in line thereof and having at least one wall to which the power stream attaches itself and two parallel enclosing surfaces which intersect said at least one wall, a control port upstream of the point of power stream wall attachment for sElectively switching the power stream therefrom, the improvement wherein said attachment wall consists of at least two wall portions, said at least two wall portions being spaced different distances from a plane which lies along the longitudinal axis of said power stream and is perpendicular to said enclosing surfaces, whereby a relatively low pressure fluid control signal at said control port causes said power stream portion attached to the wall portion most remove from said plane to detach and to pull the remaining portion of said power stream from said other wall portion.
 2. The fluid amplifier as claimed in claim 1 wherein said interaction region comprises spaced diverging sidewalls and is I-shaped in cross-sectional configuration.
 3. The wall attachment fluid amplifier as claimed in claim 1 wherein said inlet nozzle includes opposed converging sidewalls and wherein said converging sidewalls have multiple wall portions corresponding to the attachment wall portions within said interaction region.
 4. The wall attachment fluid amplifier as claimed in claim 1 wherein said interaction region includes opposed, diverging, planar sidewalls having a central wall portion offset laterally towards the center of said interaction region to form upper and lower laterally displaced sidewall portions adjacent said enclosing surfaces of said interaction region to create flow regions adjacent the top and bottom wall portions which are relatively wide with respect to the flow region between the central sidewall portions.
 5. The fluid amplifier as claimed in claim 4 including opposed control ports on respective sides of the power stream, downstream of the inlet nozzle and upstream of the wall attachment points for said power stream in the absence of a control signal.
 6. The fluid amplifier as claimed in claim 5 wherein said inlet nozzle includes serpentine sidewalls having laterally spaced sidewall portions and is I-shaped in cross section, corresponding to that of said interaction region.
 7. The fluid amplifier as claimed in claim 1 wherein said interaction region comprises spaced diverging sidewalls and is T-shaped in cross-sectional configuration.
 8. The fluid amplifier as claimed in claim 7 wherein the inlet nozzle includes serpentine sidewalls having laterally spaced sidewall portions and is T-shaped in cross section corresponding to that of said interaction region.
 9. The fluid amplifier as claimed in claim 1 wherein the interaction region comprises spaced diverging sidewalls and is cross-shaped in cross-sectional configuration.
 10. The fluid amplifier as claimed in claim 9 wherein said inlet nozzle includes serpentine sidewalls having laterally spaced sidewall portions and is cross-shaped in cross section corresponding to that of said interaction region. 